Topography of a crater formed by the action of a laser pulse on the surface of a metal

An investigation was made of the factors governing the topography of a crater formed by a millisecond laser pulse on the surface of a metal sample. A model was used to account for the initial stage of the formation of such a crater and for the relief of the 'outer' zone of the damage region. Estimates were obtained of the velocities of metal droplets ejected from a molten bath on the surface, of the pressure causing such ejection, and of the pressure gradient in the compressed gas at the target surface.